The present invention relates to an improved sleep support surface for a hospital bed. More particularly, the present invention relates to a bed including a mattress having a plurality of bladders having adjustable internal pressures and a control system for altering the firmness or pressure in selected bladders to control the amount of pressure applied to heels of a patient lying on the bed.
Certain individuals who are confined to bed for an extended period of time are vulnerable to skin breakdown on the back of the heel. Protection of the skin in this area is important if initial indications of tissue failure are observed. If the breakdown process has progressed to a point of ulceration, protection of the heel area of the patient is essential to healing.
Reducing or eliminating the time an individual spends in a supine position will protect the heel area, although it may increase the risk of skin failure on other areas of the foot and body. The current practice for protecting the heel area of a patient while in the supine position utilizes means for supporting the foot to reduce or eliminate pressure and shear on the back of the heel. Such support is often provided by placing an ordinary pillow or folded towel under a calf area of the patient""s legs. Several different foam boot designs are known that strap to the leg or foot to reduce the effects of heel pressure. In addition, a conventional mattress is known in which removable sections are provided in a foot area. All of these conventional support methods require a caretaker to add or remove components from the bed in order to control pressure on the heels of the patient. Components which are removed from the bed have the potential to get lost or mislaid. Components that are added to the bed provide an extra cost associated with the purchasing, cleaning, and disposal of the added components. There is also a cost in time for the caregiver who must go through multiple steps to initiate and maintain the support of the device.
The present invention relates to an improved apparatus and method for providing protection to the back of the patient""s heels against skin damage. Advantageously, the present invention integrates a suspension system for the foot into the mattress of the bed. A single step by the caregiver activates the suspension system. Advantageously, no components are required to be added or removed from the bed in order to reduce pressure on the patient""s heels. The suspension system of the present invention does not require removal of bed linens or disassembly of the mattress.
The suspension system of the present invention automatically transfers support of the foot to the calf so that pressure and shear forces on the back of the heel are reduced or eliminated. Transfer of support occurs either by providing a lifting force on the calf, a depression under the foot, or both. The heel pressure control apparatus and method of the present invention can be deactivated so that the mattress functions as normal. The mattress area not committed to the suspension system of the present invention may be of any design, including inner-spring, foam, water, or air support. To accommodate individuals who are different heights, or lying in different locations on the mattress, the system of the present invention advantageously provides multiple zones for controlling the pressure on the heel area. The caregiver can select whichever zone provides optimal suspension based on the location of the individual""s feet on the mattress. Labels or other visual indicia are provided on a frame of the bed to facilitate selection of an appropriate zone by the caregiver. Preferably, a zone label is provided beneath each heel pressure control zone in the mattress. Since the entire heel zone pressure control apparatus is located inside the mattress, these labels provide an external, visible indication of the location of each zone.
In a preferred embodiment, the mattress includes a series of air bladders located in a foot end. Internal pressure in the chambers under the calf is increased to provide lift at the calf. A depression is simultaneously created under the foot by deflating the air chambers in the foot area. The air chambers are encased with the rest of the mattress support system in foam, which is in turn encased in ticking. Therefore, the mattress incorporating the heel management apparatus of the present invention functions and appears like a conventional mattress. Normal size bedding may be used.
According to one aspect of the present invention, a sleep support surface includes a mattress having at least two bladders located adjacent a foot end. The bladders each have a predetermined, adjustable internal pressure. The sleep support surface also includes a pressure controller configured to reduce the pressure in at least one selected bladder independently from the remaining bladders to provide pressure relief on heels of a patient lying on the mattress above the at least one selected bladder.
In the illustrated embodiment, the pressure controller further includes means for increasing the pressure in a bladder located adjacent the at least one selected bladder and located toward the head end of the mattress. This pressure increase advantageously provides the lifting force on the calves of the patient to further reduce pressure on the patient""s heels.
Also in the illustrated embodiment, the pressure controller includes a pressure sensor and an air line coupled to each of the bladders, and an air pump coupled to the air line to deflate the at least one selected bladder to a pressure of about zero psi. The pressure controller also includes means for adjusting an air volume within the at least one selected bladder at predetermined time intervals to maintain the air volume within the at least one selected bladder at about 90% or greater of the total volume of the at least one selected bladder. Illustratively, the adjusting means includes means for inflating the at least one selected bladder to a predetermined pressure at which the sensor can accurately measure the pressure in the at least one selected bladder, and means for deflating the at least one selected bladder back to about zero psi.
According to another aspect of the present invention, a bed includes a mattress having a head end and a foot end. The mattress includes a plurality of bladders. The bladders each have an independently adjustable internal pressure. The bed also includes a frame for supporting the mattress, and a visual indicia located on the frame beneath at least two of the bladders adjacent the foot end of the mattress to provide a visual indication of the location of each of the at least two bladders in the mattress. The bed further includes a pressure controller for selectively reducing pressure in at least one of the bladders located adjacent the foot end of the mattress based on the location of heels of a patient lying on the mattress relative to the visual indicia on the frame to provide pressure relief for on the heels of the patient.
In the illustrated embodiment, the pressure controller includes a pressure sensor coupled to each of the plurality of bladders and means for coupling the pressure sensor to the pressure controller. The pressure controller further includes an air manifold having a plurality of air outlets. Each air outlet is coupled to one of the plurality of bladders by an air line. The air manifold also has an outlet coupled to an air flow direction valve. The pressure controller further includes an air pump coupled to the air flow direction valve for selectively inflating and deflating the plurality of bladders independently.
Illustratively, the pressure controller further includes means for adjusting the volume in the at least one bladder having reduced pressure at a predetermined time interval to maintain the volume of air within the at least one bladder at about 90% or greater of the total volume of the at least one bladder. The adjusting means includes means for inflating the at least one bladder to a predetermined pressure at which a pressure sensor can accurately measure the pressure in the at least one bladder, and means for deflating the at least one bladder back to about zero psi.
According to yet another aspect of the present invention, a method is illustrated for providing pressure relief on heels of a patient lying on a bed. The method includes the steps of providing a mattress including at least two bladders located adjacent a foot end. The bladders each have a predetermined, adjustable internal pressure. The method also includes the step of selectively and independently reducing the pressure in at least one of the bladders to provide pressure relief on the heels of the patient lying on the mattress.
The illustrated method further includes the step of increasing the pressure in a bladder located toward the head end of the mattress and adjacent the at least one bladder in which the pressure was reduced during the reducing step. This pressure increase advantageously provides the lifting force under the calves of the patient to reduce further pressure on the patient""s heels.
The method still further includes the step of providing a visual indication of the location each of the at least two bladders in the mattress to facilitate selection of the at least one bladder in which to reduce pressure during the pressure reducing step, thereby providing pressure relief on the heels of the patient lying on the mattress. The illustrated method includes the step of selecting which of the at least two bladders to reduce the pressure in the reducing step based on a position of the patient""s heels on the mattress relative to the visual indication of the location of each of the bladders.
In one illustrated method, the at least two bladders are air filled bladders, and the reducing step includes the step of deflating the selected at least one bladder to a pressure of about zero psi. The method includes the step of adjusting an air volume within the at least one deflated bladder at a predetermined time interval to maintain the air volume within the at least one deflated bladder at about 90% or greater of the total volume of the at least one deflated bladder. The adjusting step includes the steps of inflating the at least one bladder to a predetermined pressure at which the pressure inside the at least one bladder can be accurately measured, and then deflating the at least one bladder back to about zero psi.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.